This thesis aims to explore the formal and functional characteristics of phraseological units in the English and Uzbek languages, providing a comparative analysis of their structure, usage, and cultural significance. Phraseological units, which are fixed combinations of words with meanings not directly deducible from the individual words, serve as an essential part of both languages, enriching communication and reflecting cultural values. The paper focuses on the structural differences between English and Uzbek phraseological units, analyzing their composition, degree of fixedness, and grammatical peculiarities. Additionally, the study examines the functional role of these units, including their use to convey emotions, social norms, and cultural concepts. The paper also discusses the challenges involved in translating these phraseological units and highlights the importance of understanding the cultural context to maintain the intended meaning. The comparison underscores the deep connection between language and culture, revealing the unique ways in which both English and Uzbek speakers express ideas through idiomatic expressions. The findings of this research provide insights into the intricacies of phraseology and emphasize the importance of phraseological units in both languages as vital tools for communication and cultural expression.